Merge WebKit r47420

6 files changed, 253 insertions, 30 deletions

diff --git a/WebCore/platform/image-decoders/ImageDecoder.cpp b/WebCore/platform/image-decoders/ImageDecoder.cpp
new file mode 100644
index 0000000..9c723cc
--- /dev/null
+++ b/WebCore/platform/image-decoders/ImageDecoder.cpp
@@ -0,0 +1,103 @@
+/*

+ * Copyright (C) 2008-2009 Torch Mobile, Inc.

+ *

+ *  This library is free software; you can redistribute it and/or

+ *  modify it under the terms of the GNU Library General Public

+ *  License as published by the Free Software Foundation; either

+ *  version 2 of the License, or (at your option) any later version.

+ *

+ *  This library is distributed in the hope that it will be useful,

+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of

+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU

+ *  Library General Public License for more details.

+ *

+ *  You should have received a copy of the GNU Library General Public License

+ *  along with this library; see the file COPYING.LIB.  If not, write to

+ *  the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,

+ *  Boston, MA 02110-1301, USA.

+ *

+ */

+

+#if ENABLE(IMAGE_DECODER_DOWN_SAMPLING)

+

+#include "config.h"

+#include "ImageDecoder.h"

+

+#include <algorithm>

+

+namespace WebCore {

+

+namespace {

+

+enum MatchType {

+    Exact,

+    UpperBound,

+    LowerBound

+};

+

+}

+

+template <MatchType type> static int getScaledValue(const Vector<int>& scaledValues, int valueToMatch, int searchStart)

+{

+    const int* dataStart = scaledValues.data();

+    const int* dataEnd = dataStart + scaledValues.size();

+    const int* matched = std::lower_bound(dataStart + searchStart, dataEnd, valueToMatch);

+    switch (type) {

+    case Exact:

+        return matched != dataEnd && *matched == valueToMatch ? matched - dataStart : -1;

+    case LowerBound:

+        return matched != dataEnd && *matched == valueToMatch ? matched - dataStart : matched - dataStart - 1;

+    case UpperBound:

+    default:

+        return matched != dataEnd ? matched - dataStart : -1;

+    }

+}

+

+int ImageDecoder::upperBoundScaledX(int origX, int searchStart)

+{

+    return getScaledValue<UpperBound>(m_scaledColumns, origX, searchStart);

+}

+

+int ImageDecoder::lowerBoundScaledX(int origX, int searchStart)

+{

+    return getScaledValue<LowerBound>(m_scaledColumns, origX, searchStart);

+}

+

+int ImageDecoder::scaledY(int origY, int searchStart)

+{

+    return getScaledValue<Exact>(m_scaledRows, origY, searchStart);

+}

+

+static inline void fillScaledValues(Vector<int>& scaledValues, double scaleRate, int length)

+{

+    double inflateRate = 1. / scaleRate;

+    scaledValues.reserveCapacity(static_cast<int>(length * scaleRate + 0.5));

+    for (int scaledIndex = 0;;) {

+        int index = static_cast<int>(scaledIndex * inflateRate + 0.5);

+        if (index < length) {

+            scaledValues.append(index);

+            ++scaledIndex;

+        } else

+            break;

+    }

+}

+

+void ImageDecoder::prepareScaleDataIfNecessary()

+{

+    int width = m_size.width();

+    int height = m_size.height();

+    int numPixels = height * width;

+    if (m_maxNumPixels <= 0 || numPixels <= m_maxNumPixels) {

+        m_scaled = false;

+        return;

+    }

+

+    m_scaled = true;

+    double scale = sqrt(m_maxNumPixels / (double)numPixels);

+    fillScaledValues(m_scaledColumns, scale, width);

+    fillScaledValues(m_scaledRows, scale, height);

+}

+

+}

+

+#endif // ENABLE(IMAGE_DECODER_DOWN_SAMPLING)

diff --git a/WebCore/platform/image-decoders/ImageDecoder.h b/WebCore/platform/image-decoders/ImageDecoder.h
index 57f8735..9256afe 100644
--- a/WebCore/platform/image-decoders/ImageDecoder.h
+++ b/WebCore/platform/image-decoders/ImageDecoder.h
@@ -1,5 +1,6 @@
 /*
  * Copyright (C) 2006 Apple Computer, Inc.  All rights reserved.
+ * Copyright (C) 2008-2009 Torch Mobile, Inc.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
@@ -140,7 +141,7 @@ namespace WebCore {
 
         inline PixelData* getAddr(int x, int y)
         {
-#if PLATFORM(CAIRO) || PLATFORM(WX)
+#if PLATFORM(CAIRO) || PLATFORM(WX) || PLATFORM(HAIKU)
             return m_bytes.data() + (y * width()) + x;
 #elif (PLATFORM(SKIA) || PLATFORM(SGL))
             return m_bitmap.getAddr32(x, y);
@@ -166,7 +167,7 @@ namespace WebCore {
             }
         }
 
-#if PLATFORM(CAIRO) || PLATFORM(WX)
+#if PLATFORM(CAIRO) || PLATFORM(WX) || PLATFORM(HAIKU)
         Vector<PixelData> m_bytes;
         IntSize m_size;       // The size of the buffer.  This should be the
                               // same as ImageDecoder::m_size.
@@ -188,9 +189,17 @@ namespace WebCore {
     // and the base class manages the RGBA32 frame cache.
     class ImageDecoder {
     public:
+        // ENABLE(IMAGE_DECODER_DOWN_SAMPLING) allows image decoders to write directly to
+        // scaled output buffers by down sampling. Call setMaxNumPixels() to specify the
+        // biggest size that decoded images can have. Image decoders will deflate those
+        // images that are bigger than m_maxNumPixels. (Not supported by all image decoders yet)
         ImageDecoder()
             : m_failed(false)
             , m_sizeAvailable(false)
+#if ENABLE(IMAGE_DECODER_DOWN_SAMPLING)
+            , m_maxNumPixels(-1)
+            , m_scaled(false)
+#endif
         {
         }
 
@@ -272,8 +281,25 @@ namespace WebCore {
         // since in practice only GIFs will ever use this.
         virtual void clearFrameBufferCache(size_t clearBeforeFrame) { }
 
+#if ENABLE(IMAGE_DECODER_DOWN_SAMPLING)
+        void setMaxNumPixels(int m) { m_maxNumPixels = m; }
+#endif
+
     protected:
+#if ENABLE(IMAGE_DECODER_DOWN_SAMPLING)
+        void prepareScaleDataIfNecessary();
+        int upperBoundScaledX(int origX, int searchStart = 0);
+        int lowerBoundScaledX(int origX, int searchStart = 0);
+        int scaledY(int origY, int searchStart = 0);
+#endif
+
         RefPtr<SharedBuffer> m_data; // The encoded data.
+#if ENABLE(IMAGE_DECODER_DOWN_SAMPLING)
+        int m_maxNumPixels;
+        Vector<int> m_scaledColumns;
+        Vector<int> m_scaledRows;
+        bool m_scaled;
+#endif
         Vector<RGBA32Buffer> m_frameBufferCache;
         bool m_failed;
 
diff --git a/WebCore/platform/image-decoders/ico/ICOImageDecoder.cpp b/WebCore/platform/image-decoders/ico/ICOImageDecoder.cpp
index e9296ad..bc4f357 100644
--- a/WebCore/platform/image-decoders/ico/ICOImageDecoder.cpp
+++ b/WebCore/platform/image-decoders/ico/ICOImageDecoder.cpp
@@ -249,7 +249,7 @@ bool ICOImageDecoder::processDirectory()
         ICON = 1,
         CURSOR = 2,
     };
-    if (((fileType != ICON) && (fileType != CURSOR)) || (idCount == 0)) {
+    if (((fileType != ICON) && (fileType != CURSOR)) || (!idCount)) {
         setFailed();
         return false;
     }
@@ -303,10 +303,10 @@ ICOImageDecoder::IconDirectoryEntry ICOImageDecoder::readDirectoryEntry()
     // matching uint8_ts) is so we can record dimensions of size 256 (which is
     // what a zero byte really means).
     int width = static_cast<uint8_t>(m_data->data()[m_decodedOffset]);
-    if (width == 0)
+    if (!width)
         width = 256;
     int height = static_cast<uint8_t>(m_data->data()[m_decodedOffset + 1]);
-    if (height == 0)
+    if (!height)
         height = 256;
     IconDirectoryEntry entry;
     entry.m_size = IntSize(width, height);
@@ -318,11 +318,12 @@ ICOImageDecoder::IconDirectoryEntry ICOImageDecoder::readDirectoryEntry()
     // this isn't quite what the bitmap info header says later, as we only use
     // this value to determine which icon entry is best.
     if (!entry.m_bitCount) {
-        uint8_t colorCount = m_data->data()[m_decodedOffset + 2];
-        if (colorCount) {
-            for (--colorCount; colorCount; colorCount >>= 1)
-                ++entry.m_bitCount;
-        }
+        int colorCount =
+            static_cast<uint8_t>(m_data->data()[m_decodedOffset + 2]);
+        if (!colorCount)
+            colorCount = 256;  // Vague in the spec, needed by real-world icons.
+        for (--colorCount; colorCount; colorCount >>= 1)
+            ++entry.m_bitCount;
     }
 
     m_decodedOffset += sizeOfDirEntry;
diff --git a/WebCore/platform/image-decoders/jpeg/JPEGImageDecoder.cpp b/WebCore/platform/image-decoders/jpeg/JPEGImageDecoder.cpp
index ae09586..2565ea6 100644
--- a/WebCore/platform/image-decoders/jpeg/JPEGImageDecoder.cpp
+++ b/WebCore/platform/image-decoders/jpeg/JPEGImageDecoder.cpp
@@ -461,11 +461,27 @@ void JPEGImageDecoder::decode(bool sizeOnly)
     }
 }
 
-static void convertCMYKToRGBA(RGBA32Buffer& dest, JSAMPROW src, jpeg_decompress_struct* info)
+static void convertCMYKToRGBA(RGBA32Buffer& dest, int destY, JSAMPROW src, int srcWidth
+#if ENABLE(IMAGE_DECODER_DOWN_SAMPLING)
+                              , bool scaled, const Vector<int>& scaledColumns
+#endif
+                              )
 {
-    ASSERT(info->out_color_space == JCS_CMYK);
-
-    for (unsigned x = 0; x < info->output_width; ++x) {
+#if ENABLE(IMAGE_DECODER_DOWN_SAMPLING)
+    if (scaled) {
+        int numColumns = scaledColumns.size();
+        for (int x = 0; x < numColumns; ++x) {
+            JSAMPLE* jsample = src + scaledColumns[x] * 3;
+            unsigned c = jsample[0];
+            unsigned m = jsample[1];
+            unsigned y = jsample[2];
+            unsigned k = jsample[3];
+            dest.setRGBA(x, destY, c * k / 255, m * k / 255, y * k / 255, 0xFF);
+        }
+        return;
+    }
+#endif
+    for (unsigned x = 0; x < srcWidth; ++x) {
         unsigned c = *src++;
         unsigned m = *src++;
         unsigned y = *src++;
@@ -489,23 +505,31 @@ static void convertCMYKToRGBA(RGBA32Buffer& dest, JSAMPROW src, jpeg_decompress_
         // G = 1 - M => 1 - (1 - iM*iK) => iM*iK
         // B = 1 - Y => 1 - (1 - iY*iK) => iY*iK
 
-        // read_scanlines has increased the scanline counter, so we
-        // actually mean the previous one.
-        dest.setRGBA(x, info->output_scanline - 1, c * k / 255, m * k / 255, y * k / 255, 0xFF);
+        dest.setRGBA(x, destY, c * k / 255, m * k / 255, y * k / 255, 0xFF);
     }
 }
 
-static void convertRGBToRGBA(RGBA32Buffer& dest, JSAMPROW src, jpeg_decompress_struct* info)
+static void convertRGBToRGBA(RGBA32Buffer& dest, int destY, JSAMPROW src, int srcWidth
+#if ENABLE(IMAGE_DECODER_DOWN_SAMPLING)
+                              , bool scaled, const Vector<int>& scaledColumns
+#endif
+                              )
 {
-    ASSERT(info->out_color_space == JCS_RGB);
-
-    for (unsigned x = 0; x < info->output_width; ++x) {
+#if ENABLE(IMAGE_DECODER_DOWN_SAMPLING)
+    if (scaled) {
+        int numColumns = scaledColumns.size();
+        for (int x = 0; x < numColumns; ++x) {
+            JSAMPLE* jsample = src + scaledColumns[x] * 3;
+            dest.setRGBA(x, destY, jsample[0], jsample[1], jsample[2], 0xFF);
+        }
+        return;
+    }
+#endif
+    for (unsigned x = 0; x < srcWidth; ++x) {
         unsigned r = *src++;
         unsigned g = *src++;
         unsigned b = *src++;
-        // read_scanlines has increased the scanline counter, so we
-        // actually mean the previous one.
-        dest.setRGBA(x, info->output_scanline - 1, r, g, b, 0xFF);
+        dest.setRGBA(x, destY, r, g, b, 0xFF);
     }
 }
 
@@ -517,7 +541,17 @@ bool JPEGImageDecoder::outputScanlines()
     // Initialize the framebuffer if needed.
     RGBA32Buffer& buffer = m_frameBufferCache[0];
     if (buffer.status() == RGBA32Buffer::FrameEmpty) {
-        if (!buffer.setSize(size().width(), size().height())) {
+        int bufferWidth = size().width();
+        int bufferHeight = size().height();
+#if ENABLE(IMAGE_DECODER_DOWN_SAMPLING)
+        // Let's resize our buffer now to the correct width/height.
+        if (m_scaled) {
+            bufferWidth = m_scaledColumns.size();
+            bufferHeight = m_scaledRows.size();
+        }
+#endif
+
+        if (!buffer.setSize(bufferWidth, bufferHeight)) {
             m_failed = true;
             return false;
         }
@@ -532,16 +566,34 @@ bool JPEGImageDecoder::outputScanlines()
     JSAMPARRAY samples = m_reader->samples();
 
     while (info->output_scanline < info->output_height) {
+        // jpeg_read_scanlines will increase the scanline counter, so we
+        // save the scanline before calling it.
+        int sourceY = info->output_scanline;
         /* Request one scanline.  Returns 0 or 1 scanlines. */
         if (jpeg_read_scanlines(info, samples, 1) != 1)
             return false;
 
+        int destY = sourceY;
+#if ENABLE(IMAGE_DECODER_DOWN_SAMPLING)
+        if (m_scaled) {
+            destY = scaledY(sourceY);
+            if (destY < 0)
+                continue;
+        }
         if (info->out_color_space == JCS_RGB)
-            convertRGBToRGBA(buffer, *samples, info);
+            convertRGBToRGBA(buffer, destY, *samples, info->output_width, m_scaled, m_scaledColumns);
         else if (info->out_color_space == JCS_CMYK)
-            convertCMYKToRGBA(buffer, *samples, info);
+            convertCMYKToRGBA(buffer, destY, *samples, info->output_width, m_scaled, m_scaledColumns);
         else
             return false;
+#else
+        if (info->out_color_space == JCS_RGB)
+            convertRGBToRGBA(buffer, destY, *samples, info->output_width);
+        else if (info->out_color_space == JCS_CMYK)
+            convertCMYKToRGBA(buffer, destY, *samples, info->output_width);
+        else
+            return false;
+#endif
     }
 
     return true;
diff --git a/WebCore/platform/image-decoders/jpeg/JPEGImageDecoder.h b/WebCore/platform/image-decoders/jpeg/JPEGImageDecoder.h
index 56e007d..4a822d7 100644
--- a/WebCore/platform/image-decoders/jpeg/JPEGImageDecoder.h
+++ b/WebCore/platform/image-decoders/jpeg/JPEGImageDecoder.h
@@ -1,5 +1,6 @@
 /*
  * Copyright (C) 2006 Apple Computer, Inc.  All rights reserved.
+ * Copyright (C) 2008-2009 Torch Mobile, Inc.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
@@ -57,6 +58,16 @@ namespace WebCore {
         bool outputScanlines();
         void jpegComplete();
 
+#if ENABLE(IMAGE_DECODER_DOWN_SAMPLING)
+        bool setSize(int width, int height)
+        {
+            if (!ImageDecoder::setSize(width, height))
+                return false;
+            prepareScaleDataIfNecessary();
+            return true;
+        }
+#endif
+
     private:
         JPEGImageReader* m_reader;
     };
diff --git a/WebCore/platform/image-decoders/png/PNGImageDecoder.cpp b/WebCore/platform/image-decoders/png/PNGImageDecoder.cpp
index d14333f..ad79fc8 100644
--- a/WebCore/platform/image-decoders/png/PNGImageDecoder.cpp
+++ b/WebCore/platform/image-decoders/png/PNGImageDecoder.cpp
@@ -1,5 +1,6 @@
 /*
  * Copyright (C) 2006 Apple Computer, Inc.
+ * Copyright (C) 2007-2009 Torch Mobile, Inc.
  *
  * Portions are Copyright (C) 2001 mozilla.org
  *
@@ -242,6 +243,9 @@ void PNGImageDecoder::headerAvailable()
             longjmp(png->jmpbuf, 1);
             return;
         }
+#if ENABLE(IMAGE_DECODER_DOWN_SAMPLING)
+        prepareScaleDataIfNecessary();
+#endif
     }
 
     int bitDepth, colorType, interlaceType, compressionType, filterType, channels;
@@ -313,7 +317,14 @@ void PNGImageDecoder::rowAvailable(unsigned char* rowBuffer, unsigned rowIndex,
     // Initialize the framebuffer if needed.
     RGBA32Buffer& buffer = m_frameBufferCache[0];
     if (buffer.status() == RGBA32Buffer::FrameEmpty) {
-        if (!buffer.setSize(size().width(), size().height())) {
+#if ENABLE(IMAGE_DECODER_DOWN_SAMPLING)
+        int width = m_scaled ? m_scaledColumns.size() : size().width();
+        int height = m_scaled ? m_scaledRows.size() : size().height();
+#else
+        int width = size().width();
+        int height = size().height();
+#endif
+        if (!buffer.setSize(width, height)) {
             static_cast<PNGImageDecoder*>(png_get_progressive_ptr(reader()->pngPtr()))->decodingFailed();
             longjmp(reader()->pngPtr()->jmpbuf, 1);
             return;
@@ -358,7 +369,7 @@ void PNGImageDecoder::rowAvailable(unsigned char* rowBuffer, unsigned rowIndex,
     * to pass the current row, and the function will combine the
     * old row and the new row.
     */
-    
+
     png_structp png = reader()->pngPtr();
     bool hasAlpha = reader()->hasAlpha();
     unsigned colorChannels = hasAlpha ? 4 : 3;
@@ -372,8 +383,27 @@ void PNGImageDecoder::rowAvailable(unsigned char* rowBuffer, unsigned rowIndex,
         row = rowBuffer;
 
     // Copy the data into our buffer.
+#if ENABLE(IMAGE_DECODER_DOWN_SAMPLING)
+    if (m_scaled) {
+        int destY = scaledY(rowIndex);
+        if (destY < 0)
+            return;
+        int columns = m_scaledColumns.size();
+        bool sawAlpha = buffer.hasAlpha();
+        for (int x = 0; x < columns; ++x) {
+            png_bytep pixel = row + m_scaledColumns[x] * 4;
+            unsigned alpha = pixel[3];
+            buffer.setRGBA(x, destY, pixel[0], pixel[1], pixel[2], alpha);
+            if (!sawAlpha && alpha < 255) {
+                sawAlpha = true;
+                buffer.setHasAlpha(true);
+            }
+        }
+        return;
+    }
+#endif
     int width = size().width();
-    bool sawAlpha = false;
+    bool sawAlpha = buffer.hasAlpha();
     for (int x = 0; x < width; x++) {
         unsigned red = *row++;
         unsigned green = *row++;